Valve lubricating system for internal-combustion engines



C. vT. DOMAN Aug. 7 1945.

VALVE LUBRICATING SYSTEM FOR INTERNAL-COMBUSTION ENGINES Filed Oct. 14, 1942 2 Sheets-Sheet l 1 v INVENTOR CARL T. DOMAN ZZ 16 i ATTORNEYS Aug. 7, 1945. c. T. DOMAN 7 2,381,339

VALVE LUBRICATING. SYSTEM FOR INTERNAL-COMBUSTION ENGINES Filed Oct. 14, 1942 2 Sheets-Sheet 2 INVENTOR. CARL T. 00mm 643134130 uronuevs Figure 1 is a fragmentary,

' Patented Au 7, 1945 VALVE LUBmoA'rmG SYSTEM Foa INTERNAL-COMBUSTION ENGINES Carl '1. Doman, Geddes, N. Y.,

cooled Motors Corporation, Syracuse, corporation of New York assignor to Air- N. Y., a

Application October 14, 1942, Serial No. 461,952

- s 2 Claims. This invention relates to lubricating systems,

,. particularly for valve. mechanisms of internal combustion engines, which engine embodies hydraulic valve lifters operated by the cam shaft to open the intake and exhaust valve, the valve lifters being .under hydraulic pressure to mainpumped by the hydraulic valve lifters is passed through longitudinal bores in the lift rods, thence through bores in the rocker arms to conduct the oil to the bearings of the rocker arms and also to the points where the rocker arms coact with the valve stems, and further has for itsobject' a means for conducting the 011 back .to the source or to the crank case from which it is pumped including the tubes which enclose the lift rodsand extend between the crank casing and the valve mechanism.

The invention consists in the novel features and in the combinations and constructions hereinafter set forth and claimed.

In describing this invention reference is had.

to the accompanying drawings in which like characters designate corresponding parts in all the views.

longitudinal, sectional view'=of.a horizontally opposed 11113611181 tain zero clearance in the valve mechanism at all its object such a lubricombustion engine of the valve-inthe head type.

Figure 2 is a plan view of the head. Figure 3 is a sectional view, partly in elevation, taken on the plane of line3-3, Figure l.

Figure 4 is a detail view of one conventional form of hydraulic valve lifter.

Figure 5 is an enlarged fragmentary view of the joint between each push rod and itsrocker I designates a cylinder of one bank of cylinders of a horizontally'opposed or flat engine; 2 the pistonworking in the cylinder; 3 the connecting rod, and l the crank on the crank shaft 5. The

' their ends or having hubs with intake and exhaust ports, as X, for connection to the intake and exhaust manifold.

The valves are operated by valve mechanism, as rocker arms l2, l3 suitably pivoted between l4 and i5 mounted on spindles l6 and I1, which are suitably mounted on the head I of the cylinder. The rocker arms are operated through mechanism, as lift rods l8 and 19 from the cam shaft. The rocker arm mechanism is enclosed by an oil tight cap. or cover 20 suitably secured to the head In. 2| designates the hydraulic valve lifters which cooperate with cams on the cam shaft 1, the motion of the lifters being transferred through the lift rods 16 and iii to the rocker arms 13 and I. The construction of the valve lifters forms no part of this invention. The valve lifters are pertinent to this invention only in so far as they have a pumping action and the oil pumped thereby or expelled therefrom under the pumping action conducted through the lift rods l8, l9 and through the rocker arms to lubricate the pivotal bearings of the rocker arms and the points where the lift rods coact with the rocker arms and the rocker arms coact with the valve stems. The valve mechanism here shown comprises a cylindrical member 22 working in a passage or bores 23 or 24 in the crank casing and an inner cylinder. or plunger chamber 25 fixed in the member or cylinder 22 and having a plunger 26 therein. which thrusts against the end of the lift rod l8 or is. The chamber in which the plunger works communicates with the interior of the outer cylinder 22 through a check-valve controlled passage 21, the plungerchamber 25 opening into a second chamber or compartment 28 in the outer member I8 and into which the oil discharges or leaks from one side of the plunger 26 to the 1 in ,the walls of the crank case and ducts 3|, 3'2

crankshaft 5 is suitably mounted in the crank case 6 of the engine. I is the cam shaft mount: ed in the crank case and geared to the cr shaft in any suitable manner.

I and 6, designate intake and exhaust poppet valves in the head ill of the cylinder, these being closed against their seats by springs in the usual manner when the opening force of the valve mechanism is released. The head is formed leading therefrom, the ducts opening at 33 into' the bores in which the valve lifters 2| operate. Pressure is applied to the oil in the passage 30 in any suitable manner. The oil passes from the crank case through the passage 30 and the branch passages 31, 32 and alsothrough the check-valve controlled passage 21 into the plunger chamber 26, where it acts on the plunger 26 to always take up any lost motion that may otherwise occur, due to variations in clearances between the lift rods and the rocker arms and the rocker arms and the valve stems, or in other words, tomaintain zero clearance. As the valves seat under the action of the springs ll, some of the oil will be forced or caused to leak past the plunger 28 into the bores in which the lifters work in advance of the lifters. This leaking action is, in effect, a pumping action which is constantly taking place and builds up during the operation of the engine, so that oil is being expelled at all times into the bores in advance of the lifters and expelled from the bores 23, 24 during the reciprocations of the lifters by the cam shaft. There are valve lifters 2| for the intake and exhaust valves, one for each, and these are located in the bores 23, 24 respectively,- which are located side by side. The duct 30 is common to the two bores 23, 24 in which the valve lifters work and is usually located in the separating wall between the two bores 23, 24. The head Ill of the cylinder is formed with a laterally or downwardly projecting flange 34 which, in the flat engine construction illustrated, extends beyond the cylinder wall at one side, as the lower side, and is opposed to the portions of the crank case in which the valve lifters are located. The lift rods I8, l9 extend through openings in this flange and thrust against the rocker arms l2, l3. The'lift rods I8, l9 are enclosed in tubes 35, 36 extending between the flange 34 and the opposing portion of thecrank case and having their ends anchored in the flange and in the crank case or in the ends of bores 23, 24.

Each lift rod I8 or I9 is formed hollow or with a lengthwise bore or passage 31 and with laterally extending inlets 38 at its inner end in the bore 23 or 24 in which the lifter works. The inner ends of each lift rod I8 is closed, as by a head 39, whichcoacts with a seat 40 at the end of the plunger. 26 of the hydraulic valve lifter. The other or outer end of each lift rod is also provided with a seat 4| coacting with a head 42 on each rocker arm. Each rocker arm is also formed with a lengthwise bore or passage 43 having lateral branches through the head "and through the end of the rocker arm at 44, where it coacts with the stem of the intake or exhaust valve. It also has an intermediate branch 45 for conducting oil to the pivotal bearing of the rocker arm on the spindle IE or 11.

Thus, during the pumping action of the valve lifter, the oil is pumped up through the inlets of the lift rods and through the passages 43 of the rocker arms, the oil in its passage lubricating the points at 42, where the lift rods coact with the heads -42 of the rockerarms and at 44 where the rocker arms coact with the valve stems and also the hubs of the rocker arms.

The oil after being so pumped runs into the cap 20 and out through the tubes 35, 36 and back to the crank case through outlet passages 46. These outlet passages are located in front of a plug or barrier 41 located in each bore 23 or 24 thence up to the lift rods as before described,

The construction here described is a modifica tion of that set forth in my pending application,

Serial Number 453,685, filed August 5, 1942, and differs therefrom in that by forcing the oil through the lift rods and bores in the rocker arms, a sump and splashing of the oil from the sump in the cap for the rocker arm mechanism is eliminated and the oil is forced to all points to be lubricated.

What I claim is:

1.- A valve lubricating system for internal combustion engines including a crank case, a cylinder, spring seated intake and exhaust valves for the cylinder, a piston, a crank shaft, and cam shaft, valve mechanism operated by the cam shaft including rocker arms, supports having bearings for the rocker arms, lift rods coacting with the rocker arms at like ends, the other ends of the rocker arms coacting with the valve stems, and hydraulic valve lifters coacting with the cam shaft and thrusting against said rods, and being of the type to which 011 is supplied under pressure and which have a pumping or leaking action during the operation of the engine, the crank case being formed with bores in which the lifters work, a casing enclosing the rocker arms, tubes enclosing the lift rods, and opening at their outer ends into the casing and communicating at their inner ends with said bores, the lift rods being hollow and having inlets at their inner ends opening into said bores, the rocker arms being formed with bores communicating with the interiors of the lift rods and arranged to discharge on the bearings for the rocker arms and at the points where the rocker arms coact with the valve stems, the bores in which the lifters work being provided with plugs dividing each transversely into two chambers, one opening into the adjacent tube and the inlet of 'the associated lift rod opening into the other, and an outlet for the oil returning through each tube communicating with the first of said two chambers. I

2. A valve lubricating system for an internal combustion engine, a cylinder, a crank case, and overhead valve mechanism, a casing for the overhead valve mechanism, tubular posts between the casing and the crank case at one side of the engine cylinder, hydraulic valve lifters actuated by the engine, movable in bores formed in the crank case and alined with the posts, the posts fitting into said bores, and push rods within the tubular posts and coacting with the valve lifters, the bores 'inwhich the lifters work having plugs therein,

each plug dividing one of the bores into two chambers, one of which contains one of said valve lifters, and one of said tubular posts opening into the other of said chambers, and outlet passages leading from the other of said chamber, the ends of-the tubular posts remote from the bores opening into the casing for'the overhead valve mechanism and serving as outlets for the oil pumped by the hydraulic valve lifters through the push rods to the valve mechanism.

CARL T. DOMAN.

CERTIFICATE or CORRECTION. Patent No. 2, 81, 9. August 7, 19L

' CARL "1. DOMAN.

' It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows Page 2, second column, lines 5 and 6, strike out 'pending application, Serial Number 155,685, filed August 5, 19142" and' insert instead --Patent No. 2,566,701, issued January 9, 1911.5"; and that the said Letters Patent should be readwith this correction therein that the same may conform to the record of the case" in the Patent Office Signed and sealed this 18th day of December, A. D. 19Li5.

Leslie Frazer *(Seal) First Assistant Commissioner of Patents 

